Worksheet demonstrating reference points in motion using a falling ball example.

Final Answer:
1. The reference point is the ground (or the floor).
2. It appears to follow a curved or straight path — actually, from the ground’s perspective, it’s a straight vertical path up and down.
3. Average speed = total distance ÷ total time. From the graph, the ball rises ~4 m and falls ~4 m → total distance = 8 m. Time from 0 s to 1.6 s → total time = 1.6 s. So average speed = 8 m ÷ 1.6 s = 5 m/s.
4. From the person on the ground, the ball’s path is a straight up-and-down path (vertical line).